[The positivity rate of specific IgE antibody to Japanese cedar pollen in Wakayama Prefecture].

The incidence of Japanese cedar pollinosis has been increasing each year in Japan. Japanese cedar pollinosis is a state of allergic response, mediated by IgE. So, it is important to know the state of sensitization against Japanese cedar pollen. The subjects were 1321 nonselective cases who were more than 16 years of age and who live in Wakayama Prefecture. Specific IgE antibodies to Japanese cedar pollen were measured by Lumiward immunoassay system. The results showed that positivity for sera class 2 or higher was 30.9%. Furthermore, the positivity in 1995 was higher than the positivity in either 1985 (13.9%) or 1990 (18.3%). The incidence of specific IgE antibody positivity was higher in males. Also the age distribution of the positivity was highest in the 20-29 years old group, and the positivity was decreased with age. We examined the kinds of factors influencing the positivity of specific IgE antibodies. However, the relation between the positivity of specific IgE antibodies and the various environmental factors was unclear.